1. Field of the Invention
The present invention relates to a foldable honeycomb structure and the method for making the same, and particularly relates to a foldable honeycomb structure made through a simple process and the method for making the same.
2. Description of the Related Art
Referring to FIG. 1, a schematic sectional view of a first kind of conventional foldable honeycomb structure is shown. The conventional foldable honeycomb structure 1 is applied to thermal insulation devices such as window curtain, and can be texture or non-texture, as shown in FIG. 2. Referring to FIG. 1, the honeycomb structure 1 is a double cell row structure, in which the reference numbers 11a, 11b, 11c, 12a, 12b and the like refer to a cell, the cells 11a, 11b, 11c refer to a first row, and the cells 12a, 12b refer to a second row.
Referring to FIGS. 3a to 3d, schematic views of a method for making the conventional foldable honeycomb structure in FIG. 1 are shown. First, a flat strip 13 with a length extending longitudinally is provided as shown in FIG. 3a. The strip 13 has a first surface 131 and a second surface 132.
Next, referring to FIG. 3b, a first longitudinal crease 14 and a second longitudinal crease 15 are formed on the strip 13, so as to define a first longitudinal margin 16, a central portion 17 and a second longitudinal margin 18 on the strip 13. Then, the first longitudinal margin 16 of the strip 13 is folded towards one side (upside) of the strip 13 along the first longitudinal crease 14, and the second longitudinal margin 18 of the strip 13 is folded towards the other side (underside) of the strip 13 along the second longitudinal crease 15, thereby forming an approximate Z-shape appearance. The first longitudinal margin 16 has a first surface 161 and a second surface 162; the central portion 17 has a first surface 171 and a second surface 172; and the second longitudinal margin 18 has a first surface 181 and a second surface 182, wherein the first surfaces 161, 171, 181 are the same as the first surface 131 of the strip 13, and the second surfaces 162, 172, 182 are the same as the second surface 132 of the strip 13.
Next, referring to FIG. 3c, a first glue line 191, a second glue line 192 and a third glue line 193 are applied longitudinally to the folded strip 13. The first glue line 191 is applied on the inside surface where the first longitudinal margin 16 and the central portion 17 are overlapped, i.e. between the first surface 161 of the first longitudinal margin 16 and the first surface 171 of the central portion 17, and the first glue line 191 is at the free end of the first longitudinal margin 16. The second glue line 192 is applied to the second surface 172 of the central portion 17 at the position where the central portion 17 and the second longitudinal margin 18 are not overlapped, and the second glue line 192 is usually at the position corresponding to half of the width of the first longitudinal margin 16. The third glue line 193 is applied to the first surface 181 of the second longitudinal margin 18, and is at the free end of the second longitudinal margin 18.
Next, referring to FIG. 3d, the glued strips 13 are stacked; the first glue line 191 is used for adhering the free end of the first longitudinal margin 16 to the central portion 17; the second glue line 192 is used for adhering the central portion 17 to a first longitudinal margin of another adjacent (underlying) strip; and the third glue line 193 is used for adhering the second longitudinal margin 18 to a central portion of another adjacent (underlying) strip. The expanded view after adhering is as shown in FIG. 1.
Referring to FIG. 4, a schematic sectional view of a second kind of conventional foldable honeycomb structure is shown. The conventional foldable honeycomb structure 2 is a four-cell row structure.
Referring to FIGS. 5a to 5d, schematic views of a method for making the conventional foldable honeycomb structure in FIG. 4 is shown. First, referring to FIG. 5a, a flat strip 23 with a length extending longitudinally is provided. The strip 23 has a first surface 231 and a second surface 232.
Then, referring to FIG. 5b, a first longitudinal crease 24 and a second longitudinal crease 25 are formed on the strip 23, so as to define a first longitudinal margin 26, a central portion 27 and a second longitudinal margin 28 on the strip 23. After that, the first longitudinal margin 26 of the strip 23 is folded towards one side (upside) of the strip 23 along the first longitudinal crease 24, and the second longitudinal margin 28 of the strip 23 is folded towards the other side (underside) of the strip 23 along the second longitudinal crease 25, thereby forming an approximate Z-shape appearance. The first longitudinal margin 26 has a first surface 261 and a second surface 262, the central portion 27 has a first surface 271 and a second surface 272, and the second longitudinal margin 28 has a first surface 281 and a second surface 282, wherein the first surfaces 261, 271, 281 are the same as the first surface 231 of the strip 23, and the second surfaces 262, 272, 282 are the same as the second surface 232 of the strip 23.
Then, Referring to FIG. 5c, a first glue line 291, a second glue line 292, a third glue line 293, a fourth glue line 294 and a fifth glue line 295 are applied longitudinally to the folded strip 23. The first glue line 291 is applied to the inside surface where the first longitudinal margin 26 and the central portion 27 are overlapped, i.e. between the first surface 261 of the first longitudinal margin 26 and the first surface 271 of the central portion 27, and the first glue line 291 is at the location corresponding to the free end of the first longitudinal margin 26. The second glue line 292 is applied to the second surface 272 of the central portion 27 at the location where the central portion 27 and the second longitudinal margin 28 are not overlapped, and the second glue line 292 is usually at the location corresponding to half of the width of the first longitudinal margin 26. The third glue line 293 is applied to the first surface 281 of the second longitudinal margin 28, and is at the free end of the second longitudinal margin 28. The fourth glue line 294 is applied to the inside surface where the second longitudinal margin 28 and the central portion 27 are overlapped, i.e. between the second surface 282 of the second longitudinal margin 28 and the second surface 272 of the central portion 27, and the fourth glue line 294 is two thirds of the width of the second longitudinal margin 28 away from the second longitudinal crease 25. The fifth glue line 295 is applied to the first surface 281 of the second longitudinal margin 28, and is one third of the width of the second longitudinal margin 28 away from the second longitudinal crease 25.
Next, referring to FIG. 5d, the glued strips 23 are stacked, wherein the first glue line 291 is used for adhering the free end of the first longitudinal margin 26 to the central portion 27. The second glue line 292 is used for adhering the central portion 27 to a first longitudinal margin of another adjacent (underlying) strip. The third glue line 293 is used for adhering the second longitudinal margin 28 to a central portion of another adjacent (underlying) strip. The fourth glue line 294 is used for adhering the second longitudinal margin 28 to the central portion 27. The fifth glue line 295 is used for adhering the second longitudinal margin 28 to a central portion of another adjacent (underlying) strip. The expanded view after adhering is as shown in FIG. 4.
The first kind of conventional double cell row honeycomb structure 1 of FIG. 1 and the second kind of conventional four cell row honeycomb structure 2 of FIG. 4 and other methods of making the same have been disclosed in U.S. Pat. Nos. 5,482,750, 5,670,000, 5,702,552, 6,319,586. The most important problem of the honeycomb structure and method for making the same described above resides in that the glue lines are between the central portions and the longitudinal margins. Taking the double cell row honeycomb structure 1 of FIG. 3c for example, the first glue line 191 is applied to the inside surface where the first longitudinal margin 16 and the central portion 17 are overlapped. During practical production process, since the first longitudinal margin 16, the central portion 17 and the second longitudinal margin 18 are very close when the strip 13 is folded as an approximate Z-shape as shown in FIG. 3b. Therefore, when the first glue line 191 is to be applied, a strip opener is required to be interposed between the first longitudinal margin 16 and the central portion 17 to open the first longitudinal margin 16, such that the gluing nozzle can go deep into the gap between the first longitudinal margin 16 and the central portion 17 to apply the first glue line 191. In this way, the strip 13 will be subjected to a force, which results in the bending deformation of the central portion 17, and thus the precision of gluing position is affected, as well as the aesthetic appearance of the final products.
Similarly, taking the four cell row honeycomb structure 2 of FIG. 5c for example, the first glue line 291 is applied to the inside surface where the first longitudinal margin 26 and the central portion 27 are overlapped, and the fourth glue line 294 is applied to the inside surface where the second longitudinal margin 28 and the central portion 27 are overlapped. The above-mentioned problem of requiring a strip opener is not yet eliminated.
Furthermore, another problem of the above honeycomb structure and method for making the same resides in that it employs the same strip, and if a manufactured honeycomb structure is desired to have two sides of different colors, the difficulty in dyeing will be increased; or if a manufactured honeycomb structure is desired to have two sides with different material properties, it is very difficult to manufacture the strip.
Consequently, there is an existing need for a foldable honeycomb structure and method for making the same to solve the above-mentioned problems.